Effect of phase transformation and intermetallic compounds on the microstructure and tensile strength properties of diffusion-bonded joints between Ti–6Al–4V and AISI 304L

Abstract

The occurrence of a phase transformation and the effect of intermetallic compounds on the microstructure and tensile strength properties of diffusion-bonded (DB) joints between Ti–6Al–4V and AISI 304L were studied in the temperature range of 875–950°C with an interval of 25°C, a bonding time of 60min and pressures of 4MPa and 8MPa. A maximum tensile strength of 242.6MPa, was observed for diffusion-bonded joints that were processed at a temperature of 900°C, bonded for 60min at a pressure of 4MPa and annealed for 2h at 750°C. Optical microscopy and scanning electron microscopy (SEM) were used to examine the grain growth and the fine details of the interface structure. Energy dispersive X-ray analysis (EDAX) and X-ray diffraction analysis (XRD) revealed the existence of intermetallic compounds and corroborated the phase transformation.